diff options
author | Kay Sievers <kay.sievers@vrfy.org> | 2012-01-05 22:41:45 +0100 |
---|---|---|
committer | Kay Sievers <kay.sievers@vrfy.org> | 2012-01-06 05:07:10 +0100 |
commit | ad29a9f14fa8b1932c0e418bfcf1c10ce6a35a33 (patch) | |
tree | 9212c3d9d937234c25d19b993664b8ed164869a5 /udev/udev-node.c | |
parent | 9fbe27d9d6dc6e4530ce904d35c74326e415e34e (diff) |
merge udev/, libudev/, systemd/ files in src/; move extras/ to src/
Diffstat (limited to 'udev/udev-node.c')
-rw-r--r-- | udev/udev-node.c | 385 |
1 files changed, 0 insertions, 385 deletions
diff --git a/udev/udev-node.c b/udev/udev-node.c deleted file mode 100644 index 31046bd713..0000000000 --- a/udev/udev-node.c +++ /dev/null @@ -1,385 +0,0 @@ -/* - * Copyright (C) 2003-2010 Kay Sievers <kay.sievers@vrfy.org> - * - * This program is free software: you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation, either version 2 of the License, or - * (at your option) any later version. - * - * This program is distributed in the hope that it will be useful, - * but WITHOUT ANY WARRANTY; without even the implied warranty of - * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the - * GNU General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program. If not, see <http://www.gnu.org/licenses/>. - */ - -#include <stdlib.h> -#include <string.h> -#include <stdio.h> -#include <stddef.h> -#include <stdbool.h> -#include <fcntl.h> -#include <unistd.h> -#include <errno.h> -#include <grp.h> -#include <dirent.h> -#include <sys/time.h> -#include <sys/stat.h> -#include <sys/types.h> - -#include "udev.h" - -#define TMP_FILE_EXT ".udev-tmp" - -static int node_symlink(struct udev *udev, const char *node, const char *slink) -{ - struct stat stats; - char target[UTIL_PATH_SIZE]; - char *s; - size_t l; - char slink_tmp[UTIL_PATH_SIZE + sizeof(TMP_FILE_EXT)]; - int i = 0; - int tail = 0; - int err = 0; - - /* use relative link */ - target[0] = '\0'; - while (node[i] && (node[i] == slink[i])) { - if (node[i] == '/') - tail = i+1; - i++; - } - s = target; - l = sizeof(target); - while (slink[i] != '\0') { - if (slink[i] == '/') - l = util_strpcpy(&s, l, "../"); - i++; - } - l = util_strscpy(s, l, &node[tail]); - if (l == 0) { - err = -EINVAL; - goto exit; - } - - /* preserve link with correct target, do not replace node of other device */ - if (lstat(slink, &stats) == 0) { - if (S_ISBLK(stats.st_mode) || S_ISCHR(stats.st_mode)) { - struct stat stats2; - - info(udev, "found existing node instead of symlink '%s'\n", slink); - if (lstat(node, &stats2) == 0) { - if ((stats.st_mode & S_IFMT) == (stats2.st_mode & S_IFMT) && - stats.st_rdev == stats2.st_rdev && stats.st_ino != stats2.st_ino) { - info(udev, "replace device node '%s' with symlink to our node '%s'\n", - slink, node); - } else { - err(udev, "device node '%s' already exists, " - "link to '%s' will not overwrite it\n", - slink, node); - goto exit; - } - } - } else if (S_ISLNK(stats.st_mode)) { - char buf[UTIL_PATH_SIZE]; - int len; - - dbg(udev, "found existing symlink '%s'\n", slink); - len = readlink(slink, buf, sizeof(buf)); - if (len > 0 && len < (int)sizeof(buf)) { - buf[len] = '\0'; - if (strcmp(target, buf) == 0) { - info(udev, "preserve already existing symlink '%s' to '%s'\n", - slink, target); - udev_selinux_lsetfilecon(udev, slink, S_IFLNK); - utimensat(AT_FDCWD, slink, NULL, AT_SYMLINK_NOFOLLOW); - goto exit; - } - } - } - } else { - info(udev, "creating symlink '%s' to '%s'\n", slink, target); - do { - err = util_create_path_selinux(udev, slink); - if (err != 0 && err != -ENOENT) - break; - udev_selinux_setfscreatecon(udev, slink, S_IFLNK); - err = symlink(target, slink); - if (err != 0) - err = -errno; - udev_selinux_resetfscreatecon(udev); - } while (err == -ENOENT); - if (err == 0) - goto exit; - } - - info(udev, "atomically replace '%s'\n", slink); - util_strscpyl(slink_tmp, sizeof(slink_tmp), slink, TMP_FILE_EXT, NULL); - unlink(slink_tmp); - do { - err = util_create_path_selinux(udev, slink_tmp); - if (err != 0 && err != -ENOENT) - break; - udev_selinux_setfscreatecon(udev, slink_tmp, S_IFLNK); - err = symlink(target, slink_tmp); - if (err != 0) - err = -errno; - udev_selinux_resetfscreatecon(udev); - } while (err == -ENOENT); - if (err != 0) { - err(udev, "symlink '%s' '%s' failed: %m\n", target, slink_tmp); - goto exit; - } - err = rename(slink_tmp, slink); - if (err != 0) { - err(udev, "rename '%s' '%s' failed: %m\n", slink_tmp, slink); - unlink(slink_tmp); - } -exit: - return err; -} - -/* find device node of device with highest priority */ -static const char *link_find_prioritized(struct udev_device *dev, bool add, const char *stackdir, char *buf, size_t bufsize) -{ - struct udev *udev = udev_device_get_udev(dev); - DIR *dir; - int priority = 0; - const char *target = NULL; - - if (add) { - priority = udev_device_get_devlink_priority(dev); - util_strscpy(buf, bufsize, udev_device_get_devnode(dev)); - target = buf; - } - - dir = opendir(stackdir); - if (dir == NULL) - return target; - for (;;) { - struct udev_device *dev_db; - struct dirent *dent; - - dent = readdir(dir); - if (dent == NULL || dent->d_name[0] == '\0') - break; - if (dent->d_name[0] == '.') - continue; - - info(udev, "found '%s' claiming '%s'\n", dent->d_name, stackdir); - - /* did we find ourself? */ - if (strcmp(dent->d_name, udev_device_get_id_filename(dev)) == 0) - continue; - - dev_db = udev_device_new_from_id_filename(udev, dent->d_name); - if (dev_db != NULL) { - const char *devnode; - - devnode = udev_device_get_devnode(dev_db); - if (devnode != NULL) { - dbg(udev, "compare priority of '%s'(%i) > '%s'(%i)\n", target, priority, - udev_device_get_devnode(dev_db), udev_device_get_devlink_priority(dev_db)); - if (target == NULL || udev_device_get_devlink_priority(dev_db) > priority) { - info(udev, "'%s' claims priority %i for '%s'\n", - udev_device_get_syspath(dev_db), udev_device_get_devlink_priority(dev_db), stackdir); - priority = udev_device_get_devlink_priority(dev_db); - util_strscpy(buf, bufsize, devnode); - target = buf; - } - } - udev_device_unref(dev_db); - } - } - closedir(dir); - return target; -} - -/* manage "stack of names" with possibly specified device priorities */ -static void link_update(struct udev_device *dev, const char *slink, bool add) -{ - struct udev *udev = udev_device_get_udev(dev); - char name_enc[UTIL_PATH_SIZE]; - char filename[UTIL_PATH_SIZE * 2]; - char dirname[UTIL_PATH_SIZE]; - const char *target; - char buf[UTIL_PATH_SIZE]; - - dbg(udev, "update symlink '%s' of '%s'\n", slink, udev_device_get_syspath(dev)); - - util_path_encode(&slink[strlen(udev_get_dev_path(udev))+1], name_enc, sizeof(name_enc)); - util_strscpyl(dirname, sizeof(dirname), udev_get_run_path(udev), "/links/", name_enc, NULL); - util_strscpyl(filename, sizeof(filename), dirname, "/", udev_device_get_id_filename(dev), NULL); - - if (!add) { - dbg(udev, "removing index: '%s'\n", filename); - if (unlink(filename) == 0) - rmdir(dirname); - } - - target = link_find_prioritized(dev, add, dirname, buf, sizeof(buf)); - if (target == NULL) { - info(udev, "no reference left, remove '%s'\n", slink); - if (unlink(slink) == 0) - util_delete_path(udev, slink); - } else { - info(udev, "creating link '%s' to '%s'\n", slink, target); - node_symlink(udev, target, slink); - } - - if (add) { - int err; - - dbg(udev, "creating index: '%s'\n", filename); - do { - int fd; - - err = util_create_path(udev, filename); - if (err != 0 && err != -ENOENT) - break; - fd = open(filename, O_WRONLY|O_CREAT|O_CLOEXEC|O_TRUNC|O_NOFOLLOW, 0444); - if (fd >= 0) - close(fd); - else - err = -errno; - } while (err == -ENOENT); - } -} - -void udev_node_update_old_links(struct udev_device *dev, struct udev_device *dev_old) -{ - struct udev *udev = udev_device_get_udev(dev); - struct udev_list_entry *list_entry; - - /* update possible left-over symlinks */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev_old)) { - const char *name = udev_list_entry_get_name(list_entry); - struct udev_list_entry *list_entry_current; - int found; - - /* check if old link name still belongs to this device */ - found = 0; - udev_list_entry_foreach(list_entry_current, udev_device_get_devlinks_list_entry(dev)) { - const char *name_current = udev_list_entry_get_name(list_entry_current); - - if (strcmp(name, name_current) == 0) { - found = 1; - break; - } - } - if (found) - continue; - - info(udev, "update old name, '%s' no longer belonging to '%s'\n", - name, udev_device_get_devpath(dev)); - link_update(dev, name, 0); - } -} - -static int node_fixup(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid) -{ - struct udev *udev = udev_device_get_udev(dev); - const char *devnode = udev_device_get_devnode(dev); - dev_t devnum = udev_device_get_devnum(dev); - struct stat stats; - int err = 0; - - if (strcmp(udev_device_get_subsystem(dev), "block") == 0) - mode |= S_IFBLK; - else - mode |= S_IFCHR; - - if (lstat(devnode, &stats) != 0) { - err = -errno; - info(udev, "can not stat() node '%s' (%m)\n", devnode); - goto out; - } - - if (((stats.st_mode & S_IFMT) != (mode & S_IFMT)) || (stats.st_rdev != devnum)) { - err = -EEXIST; - info(udev, "found node '%s' with non-matching devnum %s, skip handling\n", - udev_device_get_devnode(dev), udev_device_get_id_filename(dev)); - goto out; - } - - if ((stats.st_mode & 0777) != (mode & 0777) || stats.st_uid != uid || stats.st_gid != gid) { - info(udev, "set permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); - chmod(devnode, mode); - chown(devnode, uid, gid); - } else { - info(udev, "preserve permissions %s, %#o, uid=%u, gid=%u\n", devnode, mode, uid, gid); - } - - /* - * Set initial selinux file context only on add events. - * We set the proper context on bootup (triger) or for newly - * added devices, but we don't change it later, in case - * something else has set a custom context in the meantime. - */ - if (strcmp(udev_device_get_action(dev), "add") == 0) - udev_selinux_lsetfilecon(udev, devnode, mode); - - /* always update timestamp when we re-use the node, like on media change events */ - utimensat(AT_FDCWD, devnode, NULL, 0); -out: - return err; -} - -int udev_node_add(struct udev_device *dev, mode_t mode, uid_t uid, gid_t gid) -{ - struct udev *udev = udev_device_get_udev(dev); - char filename[UTIL_PATH_SIZE]; - struct udev_list_entry *list_entry; - int err = 0; - - info(udev, "handling device node '%s', devnum=%s, mode=%#o, uid=%d, gid=%d\n", - udev_device_get_devnode(dev), udev_device_get_id_filename(dev), mode, uid, gid); - - err = node_fixup(dev, mode, uid, gid); - if (err < 0) - goto exit; - - /* always add /dev/{block,char}/$major:$minor */ - snprintf(filename, sizeof(filename), "%s/%s/%u:%u", - udev_get_dev_path(udev), - strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", - major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); - node_symlink(udev, udev_device_get_devnode(dev), filename); - - /* create/update symlinks, add symlinks to name index */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) { - if (udev_list_entry_get_num(list_entry)) - /* simple unmanaged link name */ - node_symlink(udev, udev_device_get_devnode(dev), udev_list_entry_get_name(list_entry)); - else - link_update(dev, udev_list_entry_get_name(list_entry), 1); - } -exit: - return err; -} - -int udev_node_remove(struct udev_device *dev) -{ - struct udev *udev = udev_device_get_udev(dev); - struct udev_list_entry *list_entry; - const char *devnode; - struct stat stats; - struct udev_device *dev_check; - char filename[UTIL_PATH_SIZE]; - int err = 0; - - /* remove/update symlinks, remove symlinks from name index */ - udev_list_entry_foreach(list_entry, udev_device_get_devlinks_list_entry(dev)) - link_update(dev, udev_list_entry_get_name(list_entry), 0); - - /* remove /dev/{block,char}/$major:$minor */ - snprintf(filename, sizeof(filename), "%s/%s/%u:%u", - udev_get_dev_path(udev), - strcmp(udev_device_get_subsystem(dev), "block") == 0 ? "block" : "char", - major(udev_device_get_devnum(dev)), minor(udev_device_get_devnum(dev))); - unlink(filename); -out: - return err; -} |